Roy Plotnick has a new post over on Medium. The topic is clear representation of data. Whether the topic is geology, chemistry, physics, or economics, it's important to present data clearly and during a presentation or paper to describe it for all to understand.
When I was a graduate student, my fellow student Anne Raymond (now at Texas A&M), taught me an important lesson about discussing a graph during a presentation. She insisted that you must point at each axis and describe what it says, including describing the range of data on the axis, before discussing the content of the graphs. You should move your hand (or pointer) along the axes to make clear what information is conveyed. I have since taken her advice as gospel, use it in all my talks, and try to pass the style on to my students. And, of course, I use it while I teach.
I am currently teaching Earth System History, an upper-level-undergraduate/graduate course that I informally call “historical geology on steroids.” Instead of covering historical geology as an introductory course, I cover the subject on an advanced level, including readings of recent papers from the primary literature. Other current papers are introduced during lecture. Given the nature of the topic, almost all of these papers contain a graph in which some quantity, such as an isotope value or biotic diversity, is plotted against time. We cannot discuss rates of change without making an appropriate graph, where time is carefully calibrated. Or as the EarthTime project put it “No dates, no rates.” Unlike in the classic folk-rock song, geologists count the time.
